1. Field of the Invention
The present invention relates to a sheet stacking system and, more particularly, to a sheet stacking system having a disk.
2. Prior Art
Many different sheet stacking devices are known in the sheet feeding art. For example, U.S. Pat. No. 5,188,353, which is hereby incorporated by reference in its entirety, discloses a disk stacker having a tamping mechanism located over a sheet receiving platform for tamping side edges of the sheets as they fall off the stack. After a disk stacker stacks a set of sheets, they are typically finished with a staple, eject, offset or stack height adjust operation. If the copier or printer into which the stacker has been incorporated wishes to continue operating during the finishing operation(s), the sheets being processed and fed to the stacker must either be skipped or buffered while the finishing operation is in process. Accordingly there is a desire to provide a sheet stacking device that is capable of buffering sheets while a finishing operation is being performed on a printed or copied stack of sheets.
In accordance with one embodiment of the present invention, a document creating apparatus is provided having an image transfer system for transferring images onto sheets of material and a sheet stacker coupled to the image transfer system. The sheet stacker transports the sheets of material from the image transfer system along a paper path. The sheet stacker has a rotatable disk located along the paper path that can receive at least two of the sheets of material. A controller is connected to the rotatable disk to control the position of the rotatable disk. The controller rotates the rotatable disk to or past a sheet stacking position after the rotatable disk receives at least two of the sheets of material adjacent each other.
In accordance with another embodiment of the present invention, a sheet stacker is provided for transporting and stacking sheets of material. The sheet stacker has a rotatable disk that can receive at least two of the sheets of material. A controller is connected to the rotatable disk that can reversibly control the position of the rotatable disk. After a first sheet of material is received onto the rotatable disk by forward rotation, the controller reverses the rotation of the rotatable disk. The rotatable disk can then receive a second sheet of material adjacent the first sheet of material.
In accordance with another embodiment of the present invention, a method of stacking sheets of material in a sheet stacker is provided comprising a first step of receiving a first sheet of material on a rotatable disk. The rotatable disk is then rotated in a first direction. The rotatable disk is then rotated in a reverse direction. A second sheet of material is then received adjacent the first sheet of material on the rotatable disk. The rotatable disk is then rotated with the first and second sheets of material in the first direction.
In accordance with another embodiment of the present invention, a method of stacking sheets of material in a sheet stacker is provided comprising a first step of receiving a first sheet of material on a rotatable disk. The rotatable disk is then rotated in a first location. A second sheet of material is then received adjacent the first sheet of material on the rotatable disk. The rotatable disk is then rotated past the first location.
In accordance with another embodiment of the present invention, a method of stacking sheets of material in a sheet stacker is provided comprising a first step of moving a first sheet of material into a buffering location. The buffering location includes a rotatable disk for depositing the sheets of material at a sheet stacking position. A second sheet of material is then placed adjacent the first sheet of material. During either or both of the previous steps, a stack of the sheets in the sheet stacking position is finished or moved. The first and second sheets are then placed in the sheet stacking position after the stack of sheets in the sheet stacking position has been finished or moved.